Department of Preventive Medicine and Public Health,
School of Medicine, C/ San Francisco s/n,
University of Santiago de Compostela,
Santiago de Compostela CP 15782,
La Coruña, Spain;
alberto.ruano@usc.es.

OBJECTIVE: To investigate whether backpack weight is associated with back pain and back pathology in school children.

DESIGN: Cross-sectional study.

SETTING: Schools in Northern Galicia, Spain.

PATIENTS: All children aged 12-17.

INTERVENTIONS: Backpack weight along with body mass index, age and gender.

MAIN OUTCOME MEASURES: Back pain and back pathology.

RESULTS: 1403 school children were analysed. Of these, 61.4% had backpacks exceeding 10% of their body weight. Those carrying the heaviest backpacks had a 50% higher risk of back pain (OR 1.50 CI 95% 1.06 to 2.12) and a 42% higher risk of back pathology, although this last result was not statistically significant (OR 1.42 CI 95% 0.86 to 2.32). Girls presented a higher risk of back pain compared with boys.

CONCLUSIONS: Carrying backpacks increases the risk of back pain and possibly the risk of back pathology. The prevalence of school children carrying heavy backpacks is extremely high. Preventive and educational activities should be implemented in this age group.

The Full-Text Article:

INTRODUCTION:

Back pain is currently a health problem of
school children which can limit daily-life activities.
Sedentary lifestyle is possibly the most
important factor determining back pain among
school children. According to the 2006 Spanish
National Health Enquiry, 11.8% of students
aged 10–15 classified themselves as sedentary. [1]
Sedentarism along with lack of physical activity
contributes to a lower muscular tonicity of
the back. Some studies have shown that an individual
with back pain in adolescence is more
likely to develop low back pain in adult life or
that heavy backpacks can cause neck, shoulders
and back muscular problems, such as scoliosis.
[2, 3] Experts recommend that school children
should not carry loads exceeding 10% of their
body weight. [4]

The objective of this study is to analyse the
infl uence of backpack weight on back pain and
back pathologies.

DISCUSSION:

Children carrying the heaviest backpacks have a higher risk of
suffering from back pain and a higher risk of back pathology.
Most school children carry backpacks exceeding the recommended
weights.

Many studies have found that backpacks alter posture and
gait signifi cantly, produce modifi cations in the head–neck
angle, shoulder asymmetry and even lumbar lordosis. These
biomechanical alterations could induce the appearance of
chronic pain and back pathologies in the long term.

Between 20% and 45% of young people aged 14–18 have
back pain for more than 15 days. A study performed in
Northeast England in 2002 showed a low back pain prevalence
of 24%, with girls posing a higher prevalence compared
with boys. [5] Another study performed in Italy by Negrini and
Negrini [3] found that 11-year-old children carried backpacks as
heavy as 20% of their body weight, and also that 58.4% had
experienced back pain more than once in their lifetime.

Girls are more prone to experience back pain and back
pathology than boys, although there are no differences on
backpack weight by gender. Grimmer et al [6] observed that girls
were more prone to have changes in the craniovertebral angle
when carrying a backpack and this association became stronger
with age.

The cross-sectional design of the present study is a limitation,
as it limits the causal inference of its findings. In this
type of study, it is difficult to measure past events such as
pain lasting more than 15 days. Other factors that have not
been studied such as poor physical fitness, poor back posture,
structural scoliosis and hypermobility cannot be excluded as
the real cause of back pain. It is possible that backpacks were
carried frequently with one strap instead of two with this
fact acting jointly with weight in back pain incidence. The
strength of this study is the sample size, which allows for
precise estimations adjusted by sex, age, body mass index
and sports activity.

The results obtained have strong implications. Many children
transport excessively loaded backpacks, an excess which
would not be allowed for workers in employment. We strongly
encourage the medical and educational community to start
advising parents and school children about the risks posed
by heavy school bags and the fact that this risk can be easily
reduced.